Electrolytic process for producing characters and marks



Jan. 22, 1963 x w. SCHIEBELER 3,075,193

ELECTROLYTIC PROCESS FOR PRODUCING CHARACTERS AND MARKS Filed April 28,1958 INVENI'OR ".SCHIEBEIER AGENT United States Patent 3,075,193ELECTROLYTIC PROCESS FOR PRODUCING CHARACTERS AND MARKS WernerSchicheler, 4 Rennhachweg, Eutingcn, Baden, Germany Filed Apr. 28, 1958,Ser. No. 731,102 1 Claim. (Cl. 346-74) This invention relates toelectrical printing systems of the type employing electrolytic processprinting. Its principal object is to provide a new and improved systemof the above character wherein the speed of printing of alpha andnumeric symbols is increased and wherein the usable life of the printingstyli is lengthened.

Normally, printing, recording, and marking-processes on paper arecarried out mechanically. In the course of these processes the ink isdirectly brought into contact with the paper for effecting a more orless strong inking, depending on the intensity by which the ink isbrought into contact with the paper. In cases where only a very shortperiod of time is available for the inking process, or whenever thenecessary apparatus is required to be of a very simple type, thenecessity of employing mechanically operated components has a veryimpedimental effect. Attempts are therefore made for employing in suchcases, if possible, elements of the type operating in an iner-tialessmanner.

Electrolytic processes for producing characters and marks on paper havealready become known which are e.g. used in facsimile transmissionapparatus. According to these processes chemicals are embedded in thepaper pulp, which change their color as a result of chemical reactionswhen exposed to a current passage. These processes, however, have thedisadvantage that the recording medium must be treated in a definite waywhich has a substantial eifect upon the paper price. This fact is verydecisive in the case of apparatus consuming a considerable amount ofpaper per second (such as highspeed printing devices in combination withelectronic computers).

The present invention relates to an electrolytic process printingarrangement which is adapted to produce lines, character rasters,images, or the like without requiring a special kind of paper or anynoteworthy chemical treatmerit of the paper. In order to make the papercapable of conducting electric current it has merely to be slightlywetted or moistened with tap water or a salt solution (e.g. common-saltsolution).

In known printing systems using the electrolytic process on moistenedpaper, a single stylus having a direct current potential thereon, wasemployed. There, the stylus Was moved laterally on a longitudinallymoving paper to graphically print the path followed by the stylus. Thisarrangement had the disadvantage that the printing of an alpha ornumeric character was slow since the same stylus would be required toretrace its path several times. Also, difiiculty was encountered inobtaining small characters since the stylus, being made of tellurium,would dissolve and become short and blunt.

According to the present invention, these disadvantages are overcome byproviding a printing system wherein the stylus is made of any suitableconductive material and the contacting surface cooperating with thestylus is made of a large block of tellurium. In such arrange ment, theamount of tellurium dissolved would be negligible as regards the overalldecrease in size. Thus, the stylus would not change as a result of use.Also, a plurality of styli are provided in the present invention, allpositioned in operative relationship with the large block of tellurium.These styli are selectively energized to print all portions of acomplete character at one time.

The invention will now be described in detail with reference to thefigures of drawing comprising FIG. 1 which shows a group of stylipositioned over a large block of tellurium with a dampened paperrecording medium located therebetween, and FIG. 2 which shows anarrangernent for printing additional copies of each printed message.

Referring now in particular to FIG. 1, the value of the applied directvoltage from battery B depends on the period of time which is availablefor the inking process. It may e.g. range between 1 and 300 volts. Whencontacts S are closed, electric current is fed vertically through theplane of the paper by means of two oppositely arranged electrodes, suchas anode ASt and a cathode Te, which are adapted to establish a propercontact with the paper.

The actual inking process in the case of a current passage is efrectedby the cathode Te which, according to the invention, has to consist oftellurium. The anode may consist of any suitable metal or also ofgraphite. It is one of the properties of tellurium that it may easily bechanged into a hydrosol, i.e. that it in water may be changed in aparticularly simple way into the colloidal state. When applying in theprocess according to the described invention a direct-current voltage toboth electrodes then, at the cathode, the tellurium will dissolve in theform of ions in the water which is contained in the paper. On account offurther, very rapidly performed reactions the ions will again beconverted into elementary, but now colloidal tellurium. These colloidaltellurium particle-s remain in and on the paper and cause a darkbrown-black colouring of the paper at those points at which the directcurrent has passed through in a noteworthy density. In order to preventthe points to be H colored from leaking, the paper may only be wettedvery slightly.

in order to obtain the inking of a desired pattern or a coloring in apredetermined shape (e.g. characters), the electrodes are arranged inhorizontal and vertical rows as shown in FIG. 1. As previouslymentioned, in order to achieve the coloring or inking in the shape of aletter, either the tellurium cathode has to have the shape of therespective letter and the anode has to have a plane surface, or else theanode has to have the shape of the respective letter and the telluriumcathode has to he of the plane type. The difierence is merely to be seenin the fact that from the brittle element tellurium it is veryditficu-lt to make electrodes resembling the shape of letters or araster composed of a plurality of points, but that tellurium is verysuitable for producing plane or smooth surfaces. In both cases the kindor quality of the inking is the same. The ink is in all cases providedby the cathode; the inking itself, however, is only effected at thoseparts or points of the paper at which current passes through the anodeand tellurium cathode.

Depending on the kind of practical application, the electrodes ASt mayeither be of stationary or moving type, which are selectively connectedto the source of power supply, and may respectively consist of onestylus or be composed of several styli, capable of being energized on inany desired combination. During the inking rocess the current intensitymay either be constant or, in order to achieve diiierent degrees ofcoloring, may be varied with respect to its value. The feeding of thepaper may be effected continuously or spasmodically.

For recording e.g. a measuring curve a paper-tape may be continuouslyled over a tellurium cathode of a drumtype design. An anode designed asa pointed stylus which is mechanically connected with the measuringinstrument travels over the paper on the side not facing the drum. Whenconnecting the electrodes to the power source a line will be produced onthe paper, the course of which being determined by the respectiveposition of the anode.

Referring now to FIG. 2, if several copies of the same recording arerequired in the course of one printing operation it will only benecessary to insert two or more layers of paper such as P1 and P2,between the electrodes ASt and Te. In addition thereto a thin andslightly wetted sheet of paper P3 which has one side coated withtelluriurn (similar to the carbon paper used for typewriting purposes)may be inserted between each of said layers. The coating of telluriumwill again act as a cathode upon the next successive sheet of paper, andthus will effect the inking or colouring.

The herein described inking process is particularly suitable for therecording of measuring curves, for registering various kinds offeatures, for printing characters and for producing images, such as infacsimile recording systems.

While I have described above the principles of my invention inconnection with specific apparatus, it is to be clearly understood thatthis description is made only by way of example and not as a limitationto the scope of my invention as set forth in the objects thereof and inthe accompanying claim.

What I claim is:

An arrangement for the recording of marks and char- 4 acters in severalcopies simultaneously comprising a cathode electrode of tellurium havingan extended surface; an anode electrode comprising a two-dimensionalarray of individual conductive styli; a plurality of recording mediumlayers lying between said cathode and anode; a sheet provided on theanode side with a coating tellurium, disposed between individual layersof recording medium; each layer and sheet being slightly wetted with aconductive solution; means for applying a potential between selectedones of said styli and said cathode for forming the characters andmarks; and means for producing relative movement between the recordingmedia and said electrodes.

References (Iiterl in the file of this patent UNITED STATES PATENTS166,859 Edison Aug. 17, 1875 2,353,083 Roth 1.. July 4, 1941 2,334,534Ballweg Nov. 16, 1943 2,710,786 Tyler June 14, 1955 2,715,360 Brown Aug.16, 1955 2,728,627 Alden Dec. 27, 1955 2,869,965 Willard Jan. 20, 1959

